Certain water-soluble high molal oxyalkylated esters and method of making same



Patented Aug. 31, 1943; 2,328,062

UNITED STATES PATENT [OFFICE g 2.32am Y can-ram warm-sonnets men MOLAL OF MAKING SAME Melvin De Groote, University City, and Bernhard Keiser, Webster Groves, Mo., assignorsto Petrolite Corporation, Ltd, Wilmington, Del.-, a corporation of Delaware p ated.

'No Drawing.

rlginal application March 21, 1941.

- 11 Claims. (01. zoo-404.8)

This invention relates to a new chemical product or compound, our present application being a division of our co-pending application Serial No. 384,594, filed March 21, 1941 which subsequently matured as U. S. Patent No. 2,295,163, dated Sept. 8. 1942.

One object of our present invention is to provide a new material, compound or composition of matter, that is capable of use for various purposes, and particularly adapted for use as a demulsifler in the resolution of crude oil emulsions.

' Another object of our invention is to provide a practicable method for manufacturing said new material, compound or composition of matter.

The new chemical compoundor composition of matter which constitutes our present invention is exemplified by the acidic; or preferably, neutral ester derived by complete esteriflcation of one mole of a poiyallcylene glycol of the kind hereinafter described, with two moles of a fractional ester derived from a hydroxylated material of the kind herein described, and a polybasic carboxy acid having not over six carbon atoms.

I If a hydroxylated material, indicated, for the sake of convenience, by the formula T.OH,is reacted with a polybasic carboxy acid, which, simi-. larly, may conveniently be indicated as being of the dibasic type, by the formula HOOC.D.COOH, then the fractional ester obtained by reaction between equimolar quantities may be indicated by the following formula:

noocncoorr The polyethylene glycol may be characterized material of the kind such as heptaethylene glycol, octaethvlene glycol, nonaethylene glycol,

decaethylene glycol, to and including heptadecaethylene glycol. For convenience, these poly= ethylene glycols may be indicated by the following formula: 0H(C:H4O)-|H in which m has its previous significance and n represents-a numeral varying from 2 to 4.

Thus, the bulk of the materials herein contemparticularly for use as demulsifiers, may be indicated within. certain variations, as hereinafter stated, by the neutral ester derived by ester-' iiication of one mole of a glycol of the kind above described, witlr two moles of a fractional ester ofthe kind previously described. The formation of the compound may be indicated by the following reaction, although obviously, it is immaterial what particular procedure is employed to produce the particular chemical compound. or product:

As indicated previously, the polybasic acids employed are limited to the type having not more than six carbon atoms, for example, oxalic, ma-

lonic, succinic, glutaric, and adipic. Similarly,"

. usually concerned largely with convenience of manufacture of the finished ester, and also of the price of the reactants. Generally speaking,- the higher the temperature employed, the easier it is to obtain large-yields of the esterifled product. Although oxalic acid is comparatively cheap, it

decomposes somewhat readily at slightly above the boiling point of water. For this reason, it is more desirable to use an acid which is more resistant to pyrolysis. Similarly, when a polybasic acid is available in the form of an anhydride, such anhydride is apt to produce theester with greater ease than the acid itself. For this reason, maleic anhydride is particularly adaptable;

and also, everything else considered, the cost is comparatively low on a per molar basis, even though somewhat higher on a per pound basis.-

Succinic acid or the anhydride has many of the attractive qualities of maleic anhydride; and

this is also true of adipic acid. For purposes of brevity, the bulk-of the compounds hereinafter illustrated will refer to the use of maleicanhydride,'although it is understood that any other suitable polybasic acid may be employed. Furthermore, for purposes of conveniece, reference is made to the use of polyethylene glycols. As has been previously indicated, such glycols can be replaced by suitable polypropylene or utylene compounds.

As far as the rang of oxyalkylated compounds employed as reactants is concerned, it is our preference to employ those having approximately 8-12 oxyalkylene groups, particularly 8-12 oxyethylene groups. The preference to use the oxyethylated compounds is due, largely, to the fact that they are commercially available, and par ticularly so in'two desirable forms. The most desirable form is the so-called nonaethylene gly-' instance, there may col, which, although consisting largely of nonaethylene glycol, may contain small amounts of heptaethylene and octaethylene glycols, and possibly minor percentages of the higher homologs. Such glycols represent the upper range of distillable glycols; and they may be conveniently referred to as "upper distillable ethylene glycols." There is no particularly good procedure formal;- ing a sharper separation on a commercial scale; and it is understood that mixtures of one or more of the glycols may be employed. as well as a single glycol. As pointed out, it is particularly preferred to employ nonaethylene glycol as commercially available, although it is understood that this product contains other homologs, as indicated.

Substantially as desirable as the upper dis.- tillable polyethylene glycols, are the lower nondistillable polyethlene glycols. These materials are available in the form of a waxy water-soluble material, and the general range may vary somewhat from decato tetra-decaethylene glycol. As is well understood, the method of producing such glycols would cause some higher homologs to be formed; and thus, even in this be present some oxyethylene glycols within the higher range above indicated. One need not point out that these particular compounds consist of mixtures, and that in some instances, particularly desirable esters are obtained by making mixtures of the liquid nonaethylene glycol with the soft, waxy, lower nondistillable polyethylene glycols. For the sake of convenience, reference in the examples will -be and calculations will be to nonaethylene glycol;

-, the like, to produce soaporsoap-like materials.

based on a theoretical molecular weight of 414.

Actually, in manufacture, of the glycol employed, whether a higher distillable polyethylene glycol or a lower non-distillablepolyethylene glycol, or a mixture of the same, should be determined and reaction conducted on the basis of such determination, parthe molecular weight ticularly in conjunction with the hydroxyl or I acetyl value.

It has been previously pointed out that-it is immaterial how the compounds herein contemplated are manufactured, although we have found it most desirable to react the selected glycol or mixtures of glycols with maleic anhydride in a ratio of two moles of the anhydride for one mole of the glycol. Under such circumstances, we have found little tendency to form longer chain polymers; and in fact, if conducted at reasonably low temperatures, appears to be largely monomeric. For convenience, such intermediate product may then be considthe product of reaction,

cred as a dibasic or polybasic acid. One mole of the'intermediate so obtained is then reacted with two moles of the alcoholic material of the kind subsequently described.

It is to be noted, however, that if one prepares fractional acidic ester, then if two moles of the fractional acidic ester are reacted with one mole of the polyethylene glycol, there is no possibility for the formation of polymeric types of esteriflcation products under ordinary conditions.

The alcoholic compounds employed as reactants in one mode of manufactur of the present compounds, are fractional esters obtained by reaction between detergent-forming acids and poly-- hydric alcohols.

Detergent-forming acids are monocarboxy acids having more than 8 and not over 32 car-- bon atoms, and characterized by the fact that they combine with alkalies such as caustic soda,

acid, etc. In addition known, particularly in ascents The best examples are, ofzcourse, the higher fatty acids, such as oleic acid, stearic acid, palmltic to the higher fatty acids, other well-known members of this class include resinic acids, abietic acids, naphthenic acids, and acids obtained by the o 'dation ofpetroleum hydrocarbons and commonly referred to as oxidized wax acids. I

Generally speaking, the higher fatty acids are apt to contain from 1214 carbon atoms as a lower limit, to 18-22 carbon atoms as an upper limit. Oxidized wax acids may contain as many as 32 carbon atoms. For the sake of brevity, reference will be made to superglycerinated fats, although it is understood that similar products obtained from other detergent-forming acids, as well as fatty acids, are just as acceptable.

Superglycerinated fats can be prepared by a number of well-known procedures. One procedure is to react the fatty acid with a suitable polyhydric alcohol. Another procedure is to react an ester, for instance, a glyceride, with an excess of glycerol. Such procedure is sometimes referred to as re-esteriflcation. Other procedures include the use of ethylene oxide, ethylene chlorhydrin, glycerol monochlorhydrin, or the like. Since the manufacture of these products is welt View of their utility in a number of industries, further comment is required. However, attention is directed to a trade pamphlet entitled Polyhydric Alcohol Esters, ucts Company, 1949. This pamphlet describes numerous fractional esters derived from fatty acids which are particularly adaptable for use as reactants in the present instance. The fatty acid fractional esters therein described and of conventionally recognized definite chemical composition, are as follows: Diethylene glycol (mono) laurate, diethylene glycol (mono) myristate, diethylene glycol (mono) oleate, diethylene glycol (mono) palmitate, diethylene glycol (mono) ricinoleate, diethylene glycol (mono) stearate;

ethylene glycol (mono) laurate, ethylene glycol (mono) oleate, ethylene glycol (mono) ricinoleate, ethylene glycol (mono) stearate: glyceryl (mono) laurate, glyceryl (mono) myristate, glycerol (mono) oleate, glyceryl (mono) palmitate, glyceryl (mono) ricinoleate, glyceryl (mono) stearate; propylene glycerol (mono) laurate, propylene glycol (mono) oleate, propylen glycerol (mono) ricinoleate and propylene glycol (mono) stearate. i

The materials herein contemplated may be illustrated further by the following examples:

Acidic intermediate product, Example 1 One pound mole of nonaethylene glycol is reacted with two pound moles of maleic 1-" dride, so as to form nonaethylene glycol dihydrogen dimaleate.

Acidic intermediate product, Erample 2 A mixture of lower non-distillable polyethylene glycols, representing approximately decato tetradeca-ethylene glycol, is substituted for nonaethylene glycol in the preceding example.

Acidic intermediate product, Example 3 it does not appear that issued by the Glyco Prod- Acidic intermediate product, Example 4 Adipic acid is substituted for maleic anhydride in Examples 1-3, preceding.

Acidic intermediate product, Example Oxalic acid is substituted for maleic anhydride in Examples 1-3, preceding.

Acidic intermediate product, Example 6 Citric acid is substituted for maleic anhydride in Examples 1'-3, preceding.

Acidic intermediate product, Example 7 step. If desired, an inert gas, such as dried heating and esteriflcation' nitrogen, or dried carbon dioxide, may be passed through the mixture. Sometimes it is desirable to add an esterification catalyst, such as sulfuric acid, benzene sulfonic acid, or the like. This is the same general procedure as employed inthe manufacture of ethylene glycol dihydrogen diphthalate. See U. S. Patent No. 2,075,107, dated March 30, 1937, to Frasier.

Sometimes esterification is conducted most readily in the presence of an'inert solvent, that carries away the water of esteriflcation which may be formed, although, as is readily appreciated, such water of esterification is absent when the reaction involves an acid anhydride, such as maleic anhydride, and a glycol. However, if water is formed, for instance, when citric acid is employed, then be present and employed to carry oil the water formed. The mixture of xylene vapors and We ter vapors can be condensed so that the water is separated. The xylene is then returned to the reaction vessel for further circulation. 'Ihis is a conventional and well-known procedure and requires no further elaboration.

Composit on of matter, Example 1 Composition of matter, Example 2 Diethylene glycol monomyrlstate is substituted for diethylene glycol monolaurate in the preceding example.

Composition of matter, Example 3 Dlethylene glycol mono-oleate is substituted for diethylene glycol monolaurate in Composition of matter, Example Composition of matter, Example 4 Diethylene glycol monopalmitate is substituted for diethylene glycol monolaurate in Composition of matter, Example 1.

Composition of matter, Example 5 Diethylene glycol monoricinoleate is substi tuted for diethylene glycol monolaurate in. Composition of matter, Example 1.

n n 3 Composition of matter, Example 6 Diethylene glycol, stearate is substituted for diethylene monolaurate inComposition o1 mat ter, Example 1.

Composition of matter, Example 7 Diethylene glycol glyceryl monostearate is substituted i'or diethylene glycol monolaurate in Composition of matter, Example 1.

Composition of matter, Example 8 Ethylene glycol mono-oleate is substituted for diethylene glycol monolaurate in Composition of matter, Example 1.

Composition of matter, Example 9 Ethylene glycol monoricinoleate is substituted for diethylene glycol monolaurate in Composition of matter, Example 1.

Composition of matter," Example 10 Glyceryl monolaurate is substituted for di ethylene glycol monolaurate in Composition oi. matter, Example 1.

Composition of matter, Example 11 Glyceryl mono-oleate is substituted for dl ethylene glycol monolaurate in Composition of a solvent such as xylene may matter, Example 1.

Composition of matter, Example 12 The same procedure is tion of matter, Examples 1-11, inclusive, except that intermediate product of the kind exempli fled by Intermediate product, Example 4, is sub stituted for that in Intermediate product, Examples 1, 2 and 3.

COmposz'tion'of matter, Example 13 The same procedure is followed as in Composition of matter, Examples l-ll, inclusive, except that intermediate product of the kind ex- Composition of matter, Example 14 The same procedure is followed as in Composition of matter, Examples 1-l1, inclusive, ex-

cept that intermediate product of the kind exemplified by Intermediate product, Example 6, is substituted for that in Intermediate product, Examples 1, 2 and 3.

Composition of matter, Example 15 The same procedure is followed as in Composition of matter, Examples 1-11, inclusive, ex-- Examples 1, 2 and 3.

diluent or viscosity It is to be noted that this second step is an esterification reaction, and the same procedure is employed as suggested above in the preparation of the intermediate product. Needless to say, any particular method may be used to produce the desired compounds of the kind indicated.

the esterification reaction in the presence of a non-volatile-inert solvent which simply acts as a reducer.

In the preceding examples, attention has been directed primarily to the monomeric form, or at least, to hol, i. e.. a glycol, and the polyfunctional acid, usually a bifunctional compound, react to give followed as in Composia chain type compound, in which the adjacentacid and glycol nucleons occur as a structural unit. For instance, in' the monomeric form this may be indicated in the following manner:

acid glycol acid If, however, .one prepared an intermediate product employinglthe ratio of three moles of maleic anhydride and two moles of nonaethyleneglycol, the tendency would be to produce a product which might be indicated in the following manner:

acid glycol acid glycol acid Similarly, three moles of the glycol and four moles of the acid might tend to give acombination which may be indicated thus:

acid glycol acid glycol acidglycol acid Another way of stating the matter is that the composition may be indicated in the following manner:

' or self-emulsifiable compounds; whereas, others give cloudy solutions or sols; and the most desirable type is characterized by giving a, clear solution in water, and usually in the presence of soluble calcium or magnesium salts, and frequently, in the presence ofsignificant amounts of either acids or alkalies.

Water solubility can be enhanced in a number of ways which have been'suggestedby previous manufacturing directions, for instance:

(a) By using a more highly polymerized ethylene glycol;

(b) By using a polymeric form instead of a monomeric form in regard to the unit which forms the chain between the two alcoholic nuclei;

v(c) By using a polybasic carboxy acid of lower molecular weight, for instance, maleic acid instead of adipic acid;

(d) By using an alcoholic material of lower molecular weight, for instance, ethylene glycol monolaurate, instead of ethylene [glycol monstearate;

(e) By using a material such as diethylene glycol mono-oleate or glyceryl mono-oleate, instead of ethylene glycol mono-oleate.

In any event, it is to be noted that the compounds of the type herein contemplated are limited to the water-soluble type, i. e., those which are self-emulsifying in water, or produce a sol or a molecular solution.

Incidentally, one obvious fact may be conveniently emphasized at this point; and that is that the hydroxylated aliphatic esters of the detergent-forming acids employed to combine with nonaethylene glycol dihydrogen dimaleate or similar materials, must be of the water-insoluble type. In other words, it is not intended to include esters of the kind obtained by reaction of. ethylene oxideon oleic acid or the like with the formation of a large number of recurring ether linkages so as to obtain water solubility. g

It is to be noted that the higher fatty acids i 'aaaa'oca include blown fattyacids, or superslycermat d ,esters obtained from blown oils. As to the jspeciflc description of this particular type of me.-

terial which may be Patent No. 2,208,509, dated July 16, 1940, to

used as areactant, see U. 8.

Blair and Boydstun.

As herein used, the term "polyhdric alcohol! refers to aliphatic alcohols containing two or more hydroxyl groups, and is intended to include such compounds as glycerol, ethylene glycol, beta-methyl glycerol, 1,3 propanediol, pentamethylene glycol, alpha, beta, gamma pentanetriol, sorbitol, mannitol, and the like, and also the polyhydroxy ether alcohols,.such as ,diglycerol, triglycerol, tetraglycerol, diethylene glycol; etc. Such polyhydric ether alcosols may also be produced by ether formation from two or more different polyhydric alcohols to yield'compounds, such as ethylene glycol monoglyceryl ether, 1,3 propanediol monoethylene glycol ether, diethylene glycol monoglyceryl ether, etc. Suitable polyhydroxy ether alcohols may also be produced from a polyhydric alcohol containing three or more hydroxyls and a monohydric alcohol. Examples of such compounds are glycerol monobutyl ether, glycerol monoalkyl ether, pentanetriol monoethyl ether, diglycerol monopropyl ether, etc.

Actually, a reaction involving an alcohol and an acid (esterification) may permit small amounts of either one or both of the reactants, depending upon the predetermined proportion, to remain in an unreacted state. In the actual prepartion of compositions of the kind herein contemplated, any residual acidity can be removed by any suitable base, for instance, ammonia, triethanolamine, .or the like, especially in dilute, solution. Naturally, precaution should be taken, so that neutralization takes place without saponification or decomposition of the ester. In some cases there is no objection to the presence of the acidic group. Indeed, if a tribasic acid be employed in such a manner as to leave one free carboxyl group, then it is usually desirable to neutralize such group by means of a suitable basic material.

In the hereto appended claims, reference to a neutral product refers to one in which free carboxylic radicals are absent.

Materials of the kind herein contemplated may 'find uses as wetting, detergent, and levelingagents in the laundry, textile, and dyeing industry; as wetting agents and detergents in the acid washing of fruit, in the acid washing of building stone and brick; as a wetting agent and spreader in the application of asphalt in road building and the like, as a constituent of soldering flux preparations; as aflotation reagent in the flotation separation of various minerals; for flocculation and coagulation of various aqueous suspensions containing negatively charged particles such as sewage, coal washing waste water, and various trade wastes and the like; as germicides, insecticides, emulsifiers for cosmetics, spray oils. water-repellent textile finish, etc. These uses are by no means. exhaustive.

However, the most important phase of the present invention, as far as industrial application goes, is concerned with the use of the materials previously described as demulsifiers for water-in-oil emulsions, and more specifically, emulsions of water or brine in crude petroleum.

We have found that the particular. chemical compounds or reagents herein described and desirable for use as demulsifiers may also be used for other purposes, for instance, as a break in-.

' feet the solubility,

ducer in doctor treatment of the kind intended to sweeten gasoline. See U. S; Patent No. 2,157,223, dated May 9, 1939,'to Sutton.

Chemical compounds of the, kind herein described are also of value as surface tension depressants in bearing strata by means of strong mineral acid, such as hydrochloric acid. Similarly, some members are eifective as surface tension depressants or wetting agents in the flooding of exhausted oil-bearing strata.

As to using compounds of the kind herein scribed as flooding agents for recovering oil from subterranean strata, reference is made to the procedure described in detail in U. S. Patent No. 2,226,119, dated December 24, 1940, to De Groote and Keiser. As to using compounds of the kind herein described as demulsifiers, or in particular as surface tension depressants in combination with mineral acid or acidization of oilbearing strata, reference is made to U. S. Patent No. 2,233,383, dated February 25, 1941, to De Groote and Keiser.

give a substantially The introduction of such low molal hydrophobe groups does not seriously afand in some instances, gives increased resistance, to soluble calcium and magnesium salts, for such property is of particular value. Usually, however, neutralization with a dilute solution of ammonia or the like is just as practicable and less expensive.

In the hereto attached claims, four types of alcohols are referred to in the claims as alco-' holic intermediates" insofar that they contain an alcoholiform hydroxyl radical. The fractional termediate reactant and an alcoholic intermedi other acidic; and ant consisting of a polyalkylene glycol having at least 7 and not more than 17 ether linkages; and the alkylene radical thereof. containing at least 2 andnot more than 6 carbon atoms; and the acidic primary reactant being a polybasic carboxy acid having not more than and the ratio of the said primary esterifying reactants being within the range 6 carbon atoms;

the acidization of calcareous oil- 7 being acidic and the other alcoholic, to wit, a detergent-forming monocarboxy acid having more than 8 and not more than 32 carbon atoms and a polyhydric alcohol having at least 2 and not more than 12 carbon atoms; the ratio of intermediate reactants being two moles of the alcoholic intermediate reactant for each mole of the acidic intermediate reactant.

2. A neutral water-soluble ester, being the resultant of two intermediate reactants, to wit, an acidic intermediate reactant and an .alcoholic intermediate reactant; said acidic intermediate reactant being in turn the resultant fractional ester of two primary reactants, one being alcoholic and the other acidic; and said primary alcoand likewise, one

holic reactant consisting of a. polyalkylene glycol taining at least 2 and not more than 6 carbon atoms; and the acidic primary polybas'ic carboxy acid having not more than 6 carbon atoms; and the ratio of the said primary esterifying reactants being within the range of more than 1 mole and not polybasic acid for each mole of the polyalkylene glycol; and said intermediate alcoholic reactant being the fractional ester of two additional primary reactants, and likewise, one being acidic and the other alcoholic, to wit, a detergent-forming monocarboxy acid having more than 8 and not more than 32 carbon atoms and a polyhydric alcohol having at least 2 and not more than 12 carbon atoms; the ratio of intermediate reactants being two moles of the alcoholic intermediate reactant for each mole of the acidic intermediate reactant being a reactant.

holic and the other acidic; and said primary alcow holic reactant consisting having at least 7 and not more than 17 ether linkages; and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and the acidic primary reactant being a dibasic carboxy acid and the other alcoholic, to wit, a detergent-fenning monocarboxy acid having more than 8 and not more than 32 carbon atoms and a polyhydric alcohol having at least 2 and not more than 12 carbon atoms; the ratio of intermediate reactants being two moles of the alcoholic intermediate reactant for each mole of the acidic intermediate reactant.

4. A neutral water-soluble ester, being the reover 2 moles of the dibasic acid for each glycol having at 6 dibasic carboxy acid having not more than6 carbon atoms; and the ratio of the said primary esterifying reactants being within the range of more than 1 mole and not over 2 moles of, the

glycol; and said intermediate alcoholic reactant being the fractionalester of two additional primary reactants, and likewise, one being acidic and the other alcoholic, to wit, a detergent-forme ing monocarboxy acid having more than 8 and not more than 32 carbon atoms and a polyhydric alcohol having at least 2 and not more than 12 carbonatoms; the ration of intermediate reactants being two moles of the alcoholic intermediate reactant for each mole of the acidic intermediate reactant.

5. A neutral water-soluble ester, being the resultant of two intermediate reactants, to wit, an acidic intermediate reactant and an alcoholic intermediate reactant; said acidic intermediate reactant being in turn the resultant fractional ester of two primary reactants, one being alcoholic and the other acidic; and said primary alcoholic reactant consisting of a polyethylene least '2 and not more than 1'7 ether linkages; and the acidic primary reactant being a dibasic carboxy acid having not more than 6 carbon atoms; and the ratio of the said primary esterifying reactants being within the range of more than 1 mole and not over 2 moles of the dibasic acid for each mole of the polyethylene glycol; and said intermediate alcoholic reactant being the fractional ester of two additional primary reactants, and likewise, one being acidic and the other alcoholic, to wit, a higher fatty acid having more than 8 and not more than 32 carbon atoms and a polyhydric alcohol having at least 2 and not more than 12 carbon atoms; the ratio of intermediate reactants moles of the alcoholic intermediate reactant for each mole of the acidic intermediate reactant.

6. A chemical compound as defined in claim and of the following structural formula:

I in which '1 is the intermediate alcoholic reactant residue and D is the dibasic acid residue and m represents a numeral varying from 7 to 12 and a:

, is a small whole number less than 10.

defined in claim 5 7. A chemical compound as and of the following structural formula:

TOOC.D.COO (C2H40) mC2H4OOC.D.COO.T

mole of the polyethylene being two 8. A chemical compound as defined in claim 5 and of the following structural formula:

A being alcoholic and the hydric alcohol having in which T is the intermediate alcoholic reactant residue and D is a maleic acid residue and 111 represents a numeral varying from '1 to 12.

9. A chemical compound as defined in claim 5 and of the following structural formula:

I TOOC.D.COO (C2H4O) mC2H4OOC.D.COO.T in which T is the intermediate alcoholic reactant residue and D is an adipic acid residue and m represents a numeral varying from '7 to 12.

11. In the manufacture of a water-soluble ester, being the resultant of two intermediate reactants, to wit, an acidic intermediate reactant and an alcoholic intermediate reactant; said acidic intermediate reactant being in turn the resultant fractional ester of two primary reactants, one other acidic; and said primary alcoholic reactant consisting of a polyalk'ylene glycol having at least '7 and not more than 17 other linkages; and the, alkylene-radical thereof containing at least 2 and not more than 6 carbon atoms; and the acidic primary reactant being a polybasic carboxy acid having not more than 6 carbon atoms; and the ratio of the said primary esterifying reactants being within the range of more than 1 mole and not over 2 moles of the polybasic acid for each mole of the polyalkylene glycol; and said intermediate alcoholic reactant being the fractional ester of two additional primary reactants, and likewise, one being acidic and the other alcoholic, to wit, a detergentforming monocarboxy acid having more than 8 and not more than 32 at least 2 and not more than 12 carbon atoms; the ratio of intermediate reactants being two moles of the alcoholic intermediate reactant for each mole of the acidic intermediate reactant, the steps of: (A) esterifying the polyhydric alcohol with the detergentforming monocarboxy acid to yield the alcoholic intermediate reactant; (B) reacting the polyalkylene glycol with the polybasic carboxy acid to yield the acidic intermediate reactant; and (C) subsequently reacting said intermediate reactants to yield the water-soluble ester.

MELVIN DE GROOTE. BERNHARD KEISER.

carbon atoms and a poly-v 

